<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    * {
      margin: 0;
      padding: 0;
    }
    body {
      display: flex;
      justify-content: center;
      align-items: center;
      height: 100vh;
      background-color: #222;
    }
    .container {
      display: flex;
      justify-content: center;
      align-items: center;
      height: 100%;
      width: 100%;
      background-color: #222;
      animation: animateBg 10s linear infinite;
    }
    .loading {
      position: relative;
      width: 120px;
      height: 120px;
    }
    @keyframes animateBg {
      0% {
        filter: rotate(0deg);
      }
      100% {
        filter:  rotate(360deg);
      }
    }
    .loading span {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      transform: rotate(calc(18deg * var(--i)));
    }
    .loading span::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      width: 15px;
      height: 15px;
      border-radius: 50%;
      background-color: #00ff0a;
      box-shadow: 0 0 10px #00ff0a,
                  0 0 20px #00ff0a,
                  0 0 40px #00ff0a,
                  0 0 60px #00ff0a,
                  0 0 80px #00ff0a,
                  0 0 100px #00ff0a;
      animation: animate 2s linear infinite;
      animation-delay: calc(0.1s * var(--i));
    }
    @keyframes animate {
      0% {
        transform: scale(1);
      }
      80%,100% {
        transform: scale(0);
      }
    }
  </style>
</head>
<body>
  <div class="container">
    <div class="loading">
      <span style="--i:1;"></span>
      <span style="--i:2;"></span>
      <span style="--i:3;"></span>
      <span style="--i:4;"></span>
      <span style="--i:5;"></span>
      <span style="--i:6;"></span>
      <span style="--i:7;"></span>
      <span style="--i:8;"></span>
      <span style="--i:9;"></span>
      <span style="--i:10;"></span>
      <span style="--i:11;"></span>
      <span style="--i:12;"></span>
      <span style="--i:13;"></span>
      <span style="--i:14;"></span>
      <span style="--i:15;"></span>
      <span style="--i:16;"></span>
      <span style="--i:17;"></span>
      <span style="--i:18;"></span>
      <span style="--i:19;"></span>
      <span style="--i:20;"></span>
    </div>
  </div>
</body>
</html>